The Bibliotheca Neerlandica Manuscripta (BNM) collects and makes available information on medieval manuscripts produced in the Netherlands regardless where they are kept. Documentation activities concentrate on the Middle-Dutch texts and their authors that have been transmitted in these manuscripts, on the individuals and institutions that have been involved in the manuscript production (scribes, illuminators, monasteries) and on the former and present manuscript owners.

The manuscript descriptions — kept in folders and boxes that are placed in two bookcases (approximately 8 metres) — are arranged by location and shelfmark. The textual, codicological and book-historical data of these descriptions have been noted down on cards and arranged in several card indexes. There are three important files: authors and textual headwords; scribes and owners; scriptoriums and libraries. The descriptions and card files can be consulted in the University Library. Visitors are requested to report to the desk of the Special Collections Reading Room.

Since 1991 two-thirds of this ‘paper’ information, checked and supplemented with information from recent publications, has been converted into electronic data and incorporated in a database, which can be searched on the internet. In 2007 this BNM database became available in a new configuration. The user’s manual — with information on search keys, search strategies and the design of the database — can be consulted while searching the database (please use the Help-button).

The Bibliotheca Neerlandica Manuscripta only includes published information after mentioning its source. Likewise, users should make proper reference to the BNM in their publications, when they have used it to their benefit.

The BNM was set up as a personal research tool by Willem Lodewijk de Vreese (1869-1938). This Flemish scholar realized that Middle-Dutch texts could only be studied thoroughly after building an information corpus that should cover all the manuscripts in which those texts are transmitted. For that purpose he visited hundreds of libraries in Belgium, the Netherlands, Germany and elsewhere in Europe, and compiled thousands of manuscript descriptions. Tens of thousands textual, codicological and book-historical data have been written on cards and incorporated in the indexes.

After his death the Dutch government bought the BNM and housed it in Leiden University (1939). The documentation system — consisting of folders and boxes with descriptions, card indexes, photographs and rubbings of tooled bindings — was kept and expanded as a part of the former Western manuscripts Department (now Special Collections Division).

In 1991 the Netherlands Organization for Scientific Research (NWO) acknowledged the BNM as a national centre of expertise. A year later NWO and the former Ministry of Education and Science (O&W) subsidized a project in which a considerable part of the textual, codicological and book-historical data from the card files has been analyzed, updated and incorporated in a database accessible to all interested users (retro project 1992-1995). In 1997 NWO subsidized a second project, in which the data of small texts and former owners was analyzed, updated and incorporated in the database (Retro project 1997-2000). At this moment about two-thirds of the information in the card files has been updated and made available in the database.